Disk space 6Mb for the system plus that required for data @
approximately 1200 samples per Mb

Installation of Microsoft Word, Excel and
Outlook (or Outlook Express) is recommended but not essential.

System operation

While representing a complex and powerful tool for the
engineer the Gradlab system is easily accepted and used by junior, or formerly
non-computer literate personnel. On-line tip based help is provided and this
makes extensive training or constant reference to written manuals unnecessary.

System structure

The Gradlab Gds system consists of four main databases and
a suite of programs to manipulate them. The databases represent Samples,
Material specifications, material Suppliers, and Jobs (i.e. material
destinations). As Sample records are entered into the Sample database they are linked
to records previously entered into the other three, this
structure allows Sample test results to be separated and analysed based upon any
combination of Material specification, Supplier or Job the user selects. The system is
able to meet the needs of users in quarry, site and central laboratory
environments. DataSet Structure.
Multiple datasets are supported. The system supports zipped backup, unzipped
duplication and email of datasets.

Material specification input and storage

Individual specifications for each material are entered into
the Gradlab material database using the Material browser prior to entry of sample data
representing them. Specification types for soil, drystone aggregate, and
bituminous paving materials are supported. Materials can be specified/
tested on up to 18 sieves. The Material browser also
facilitates modification of existing material records and calculation of
statistics relating to their source, destination and sample compliance.
Assignment of materials to Q Value Groups and subsequent analysis is supported. OCL
statistical analysis to BS EN 13108-21 is supported. CE, Type Testing and Declaration of
Performance certificates can be produced.

Supplier information input and storage

Information regarding each source of materials is entered
into the Gradlab supplier database using the Supplier browser before input of related
sample data. In addition to name and aggregate type, supplier records
accommodate storage of supplier postal address and characteristic test results.
The Supplier browser also facilitates modification of existing supplier records
and calculation of statistics relating to Materials supplied, Jobs supplied and
sample compliance.

Job information input and storage

Data for each job from which materials are being sampled are
entered into the Gradlab job database via the Job browser prior to input of related
sample records. Job records store the job postal address/ phone number and
account number. The Job browser also facilitates preparation of statistics for
the Materials supplied, Suppliers used and related sample compliance.

Sample record input, storage and calculation

Sample records store data for sieve analysis tests, other result
data e.g. temperature, binder content, and flakiness can be included. Details for samples may be entered into the Sample
browser on their receipt to the
laboratory and custom laboratory test forms produced for them. Information can
be entered onto the system as pre-calculated results or as laboratory source
data, in the latter case results are calculated from the source data when sample
records are retrieved. The user is alerted if sample start weights or sieve
loads are outside predetermined limits. Drystone aggregate samples may be
entered using dry or wash grading methods. Blacktop (Bituminous or Tar based)
material samples may be entered using binder by difference (pressure filter),
aliquot (binder direct) and loss by ignition test methods. Computation of
aliquots, solvent weights and riffle factors is supported. The calculations
performed and corrections applied to calculate sample results are determined by
the test method employed and the material specification type represented. Sample
results are categorised using the Mercia QA scheme for coated materials which
coincides with that currently specified by The National Third Party QA scheme
for The Production of Asphalt Mixes.

Sample reporting

Result data for completed sample records can be reported in a
variety of text and graphical formats. Individual samples can be displayed,
printed out and emailed as;

Distribution graph for each specified sieve or test parameter
including specified envelope.

Running mean trend graph for each tested parameter.

Pie chart indicating compliance category for sample results.

Analytical capability

The analyses produced allow the user to assess the actual
compliance of samples with regard to material specifications and the category
scheme employed. Additionally statistical information regarding expected
compliance can be assessed and compared with the actual figures. Test parameters
which exhibit poor control can be quickly identified and appropriate actions
taken, in many cases, before actual non compliance occurs.

Facilitates automatic and manual blending of a number of
aggregates into a combination to satisfy a given target gradation envelope.
Automatic blending is achieved using a non-iterative mathematical technique
which is fast and reliably reproduces the exactly the same result from a given set of data.
The module is popular with supplier based users who need to combine
aggregates from a number of single-size bins or stockpiles into a blend that meets specified
gradation limits, it is also of value in trial mix design work. Target
gradations can be selected from any existing in the Gradlab sample/ material databases or
entered manually.

Enables statistics to be produced for 'blacktop' materials on
a global basis including multiple materials and material types, the standard
system allows analysis of single materials only. Analysis focuses on parameters
common to all 'blacktop' materials, namely binder content, fines content, filler
content, and temperature. Trend, distribution and cusum graphs/ statistics can
be produced for each parameter with reference to specified mean values and or
user defined targets.

This module enables cusum analysis to be used to control
binder, fines and filler content statistically for selected supplier/ blacktop
material types. Indication is given when a parameter is out of control, and by
how much, thus a control feedback loop can be maintained. Cusum analysis can be
easily performed as each ‘blacktop’ sample is entered and ‘breakpoints’
created when adjustments are required. At breakpoints the cusum chart trace
restarts at zero and comments can be stored explaining why they have been made.